Evaluation of the toxicity of essential oil components on Varroa destructor (Acari: Varroidae) and Apis mellifera (Hymenoptera: Apidae).

BRASESCO C; MAGGI M.D; NEGRI P; GENDE L.; RUFFINENGO S; SZAWARSKI N.; EGUARAS M.

Buenos Aires

Congreso; 2012 International Congress on Invertebrate Pathology and Microbial Control and 45th Annual Meeting of the Society for Invertebrate Pathology; 2012

Society for Invertebrate Pathology Officers

The parasitic mite Varroa destructor is considered to be one of the most serious pests of the honey bee Apis mellifera, causing great economic losses to the beekeeping industry. Historically, syntheticacaricides such as pyrethroids and organophosphates have been the miticides of choice for mite control in apiaries. Nevertheless its widespread use, and often its misuse throughout those years, has placed a strong selective pressure on mite populations, and therefore, resistant populations have emerged in several countries worldwide. Alternative acaricides offer a highly desirable alternative to the synthetic products. In adition, information about toxicity of essential oil components against A. mellifera and V. destructor is still scarce. The lethal effects (LC50) of mircene, carvacrol, phellandrene, cinnamic aldehyde, eucalyptol and thymol were assessed in this work. The acaricidal effects (LC50) of thymol and phellandrene against V. destructor were tested also. These components were selected due they are the major components of essential oils that showed promisors acaricidal effect on Varroa mites in previous researches. Bioassays were performed to assess oil components toxicity by total exposure over bees and mites at 24, 48 and 72 h. Results showed that essential oil components differ in their bioactivity against the target arthropod. Thymol and carvacrol was the most toxic components for A. mellifera while eucalyptol and phellandrene were the less toxic for bees. With regard mite toxicity thymol was the most toxic component for the parasite. Oil components bioactivity against mites demonstrates that these substances represent a great alternative for future formulations for V. destructor control